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It's pretty widely known that what someone does while they're pregnant can affect their baby in big ways. Like, you might have heard how pregnant people should stay away from certain foods, like some kinds of raw fish, because of the potential negative health effects.

But it turns out that a pregnant person's diet could have less significant effects on their baby, too. Some research suggests that what they eat during pregnancy might affect the flavors their child likes even years after birth. So whether you're a huge fan of garlic or can't get enough of sugary cereals, your time in the womb might be at least partly responsible.

We experience flavors mainly thanks to our senses of taste and smell, specifically, to the taste receptors in our mouths and the smell receptors in our noses. In the womb, these cells begin developing pretty early, sometime around the first trimester. But since a fetus gets its nutrients through blood vessels in the umbilical cord, it might seem like these cells just don't experience much for a while.

Except, they totally do. See, during development, a fetus is surrounded by a protective liquid called the amniotic fluid. As they grow, they start to frequently inhale and swallow this stuff, and it's not just some tasteless goop.

Research has shown that what a pregnant person eats can actually affect how this liquid smells and tastes. For example, a study published in 1995 in Chemical Senses found that when five pregnant women took garlic pills, samples of the amniotic fluid from four of them smelled like garlic. And other studies with different flavors have found similar results.

Now, we can't say for sure that fetuses can actually recognize the taste of this fluid. But they have been observed swallowing more of it when it tastes sweeter, and less when it tastes bitter, which suggests they might know what's going on. Either way, we can definitely say that before birth, their taste and smell receptors are getting drenched in this stuff.

But just because you're exposed to the taste of garlic during development doesn't necessarily mean you'll come into the world craving pasta. To figure that out, researchers have also investigated whether so-called prenatal taste experiences can have lasting effects even after birth. The main study on this, which was published in the journal Pediatrics, came out in 2011, and it looked at almost 50 pregnant women, divided into three roughly equal groups.

One group drank carrot juice several times a week for three weeks during their last trimester. Another drank water during pregnancy but carrot juice while they were nursing, since flavor can also be transmitted through breast milk. And the third group just drank water.

Once their babies were a few months old and starting to eat solid food, the moms brought them into the lab, and the babies were recorded eating two types of cereal. One type was unflavored, and the other was flavored with carrot juice. Then, the researchers had the moms, who weren't told the point of the study, rate how much they thought their kids enjoyed the food.

Carrot cereal sounds pretty gross, but it turned out that the babies who were exposed to that flavor in the womb were rated as liking it more than the other two groups of kids. This was backed up by video recordings of the taste test, too. Overall, babies who had been exposed to the carrot flavor before birth, or during nursing, made significantly fewer negative faces in the first two minutes of the taste test when eating that cereal.

So, what pregnant people might actually affect how much their baby enjoys certain foods. In a way, this isn't that surprising, because we all tend to like things that we're familiar with. But the fact that this whole process begins before you're even born is pretty mind-blowing.

Like, these babies enjoyed carrots before they had eaten a single piece of actual food. Of course, this study is really the only one that's explored prenatal taste experiences so far, so more research would help prove this. But there have been more studies done about how what a baby eats early in life can affect their preferences.

And those effects seem to last well into childhood. Most of these studies focused on breast milk and formula. People who are breastfeeding tend to have diets that include lots of different flavors.

And since flavors are passed through the milk, that means their baby experiences them, too. Some studies have shown that this early variety is linked to kids eating more vegetables, or at least being willing to try them, when they're as old as six or seven. Basically, the idea is that because they experienced so many tastes in infancy, they're more willing to try new flavors when they're older.

Kids who are given formula tend to have a less varied taste experience, but research shows that formula affects their taste development, too. Like, one 2010 study with more than 800 ten-year-olds found that the kids who were fed a certain formula as babies were more willing to accept a similar flavor than kids who were fed something else as infants. All this suggests that what your parent ate during pregnancy, or what you were fed shortly after birth, can have surprisingly long-lasting impacts on your life.

There aren't studies looking at how this all applies to, say, college students, and there are plenty of other things that go into your favorite foods, like sociocultural factors, genetics, and even how the food is presented. But the next time you're cooking up a big batch of carrots or some garlicky pasta, know that this might have something to do with what you were eating before you were even born! Thanks for watching this episode of SciShow Psych!

If you'd like to learn more about your sense of taste, and the surprising psychology that affects it, you can watch our episode about how restaurants might be using psychology to trick you. [♩OUTRO].